Because that's patently absurd. That would cripple their own use of their own search engine.
However, that's not to say that there aren't necessarily some..."people"...at Google who would try to pursue such a patently absurd outcome. Maybe we need to give more serious consideration to these "distributed search engine" projects...
Desktop users block ads. Mobile users don't.
I do. Anyone who root's their phone can easily block ads.
So why don't they do that? It should be super simple to do -- just do it! Likewise, here, it should be easy to get to the other link. I don't get their thinking here. (Plus, mobile versions of browsers should be basically as functional as normal browsers these days, so it's not like that's a good reason. Mobiles run desktop versions of sites just fine -- wasn't there just an article saying that the iPhone 7 is faster at single-core CPU tasks than any Macbook Air ever made?)